B. Tolibjonov, Sh. Samandarov, D.Umirzakova, and Y.Yunusova. “Teaching and Learning Foreign Languages in Uzbekistan. CEFR: Learning, Teaching and Assessment”. International Journal on Integrated Education, Vol. 3, no. 1, Mar. 2020, pp. 57-61, doi:10.17605/ijie.v3i1.40.